Gripper mechanism



R. H. LAWSON GRIPPE'R MECIHANISM y' Nov. 30, 1948.

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` GRIPER MEcHANIsM Filed-Feb. 28, 1947 3 Sheets-Sheet 2 foberzf H Lawson y his A ttor/zeg l v R. H. LAWSON GRIPPER MEcHANrsM' Nov. so, 194s.

s sheetsLsheet s med Feb. 28, 1947 .By his Attorney Patented Nov. 30, i948 GRIPPER IVJIECHANISM Robert H. Lawson, Beverly, Mass., assignor to United Shoe Machinery Corporation, Flemington, N. J., a corporationl of New `lersey Application February 28, 1947, Serial No. 731,489

12 Claims.

This invention relates to gripper mechanism for tensioning multi-ply shoe uppers over lasts, and is herein illustrated as applied to upper-tensioning mechanism of the type disclosed in United States Letters Patent No. 2,201,866, issued in my name on May 21, 1940. However, it is to beunderstood that in various novel aspects the invention is more generally applicable to gripper mechanisms of other types, -and in some aspects also to gripper mechanisms for performing operations other than lasting operations.

In the lasting of multi-ply shoe uppers, for example those including an upper form-ed of leather and a fabric lining, either in a machine which, like that of the aforementioned patent, operates simultaneously at the opposite sides of a shoe, or

in a machine that operates at one side of the shoe at a time, it is frequently difcult, if not impossible, properly to tension the upper materials over the wooden last by means of a single gripper which grips both the upper and the lining. This is partly due to the different elastic characters of the two materials out of which the upper and lining are formed and also because, when the upper materials are assembled on the last, the lining being less stiff than the upper may become wrinkled or folded and more loosely fitted t0 the last. Thereafter, when the upper materials are tensioned, the leather upper may not stretch sulciently, under the pull applied by the gripper, to permit movement of the gripper necessary to remove the wrinkles from the lining and tension it smoothly over the last. Inasmuch as such wrinkles or folds in the lining will be visible in the finished shoe, it is essential to satisfactory lasting that they be removed.

It is7 therefore, an object of this invention to provide a novel gripper mechanism for tensioning a multi-ply shoe upper, including an upper and a lining, over a last, in such a manner that all looseness in the lining will be eliminated and all wrinkles or folds therein removed before the upper materials are finally tensioned over the last. With this end in view and in accordance with a feature of this invention, the herein illustrated gripper mechanism comprises two grippers, each adapted to engage both the liningr and the upper, together with a common operating means and connections between this operating means and the two grippers so constructed and arranged as to cause the grippers, successively, to close on the upper materials and move in a heightwise direction away from the bottom of the last to tension the materials. More particularly, the improved gripper mechanism comprises an upper-tensioning gripper having a pair of jaws each provided with a toothed, or otherwise roughened, operating face for engaging the upper materialsl and movable to tension the materials over a last, herein illustrated as being of the type associated with the lasting machine illusthe bottom of the last by trated in the above-mentioned patent, and a lining-pulling gripper including a pair of jaws one of which has a smooth face for engaging the upper and the other a toothed, or otherwise roughened face, for engaging the lining and operable to tension the lining before the operation of the upper-tensioning gripper. i

Preferably, and as herein illustrated in accordance with further features of the invention, the jaws of the lining-pulling gripper, which are pivotally connected and slidably supported on the upper-tensioning gripper, are operatively connected to the common operating means'by means of a latch. These jaws are movably held in open position, against the action of yieldable closing means, by means of a cam portion formed on the operating means, which cooperates with inclined surfaces on the jaws and the latch is arranged to afford a. lost motion connection so that, as a result of the movement of the operating means these jaws are first yieldingly closed on the upper materials and then moved bodily in a heightwise direction away from the `bottom of the last, to tension the lining, before the uppertensioning gripper is closed on the upper materials. Separate cam means are also provided for releasing the' latch, to disconnect the lining-pulling gripper from the operating means, and for opening these jaws just as the upper-tensioning gripper is closed and moved bodily away from the continuedmovement of the operating means. Upon reversal of the direction of movement of the operating means, both pairs of jaws are opened and returned to positions` for engaging the next succeeding v, portion of the upper materials. As a result of roughened surface of the above arrangement, the lining is first tensoned so as to eliminate all looseness therefrom and to` remove all wrinkles or folds, by the lining-pulling gripper, the lining, `gripped by the one jaw, then moving relatively to the upper over which the smooth .sur` face of 'the other jaw readily slips, before the upper-tensioning gripper is closed and, thereafter, moved by the operating means to tension the materials over the last with both the upper and lining firmly gripped by the rcughened surfaces of both of its jaws.

These and other objects and features of the invention will appear in the following detailed description of the preferred embodiment thereof. illustrated in the accompanying drawings and will be pointed out in the claims.

In the drawings,- f

Fig. 1 is a view in side elevation of a lasting unit embodying the improved tensioning mechae nism of this invention;

Fig. 2 is a view in front elevation of the lasting unit illustrated in Fig. 1; Figs. 3, 4 and 5 are views illustrating diiferent successivevpositions of the parts of the tension.l

ing mechanism in the operation of the machine; and

Fig. 6 is an exploded view, in perspective, of the tensioning mechanism.

Referring to the drawings, the lasting unit therein illustrated comprises tensioning mechanism, including an upper-tensioning gripper having jaws 20 and 22 for seizing and tensioning the upper materials, herein illustrated as an upper U and lining L assembled with an insole I on a last A, and a lining-pulling gripper having jaws 2| and 23 for tensioning the lining; a fastenerinserting nozzle 24 for driving a fastening such, for example, as a staples, through the tensioned upper materials and a rib R` of the insole; and an anvil 25 for supporting the rib and for positioning the lasting unit during the operation of the lasting unit and for `clenching the ends of the staple legs on the inner face of the rib. These various elements are mounted on a head construction formed by embracing side plates 20, 28 which are joined to a cylindrical supporting member 30.

The gripper jaws 20, 22 and 2 I 23 are operated by means of the vertical reciprocation of a slide 32 to which is connected, by a stud 33, an operating link 34 having a bifurcated lower end 35. The gripper jaws 20, 22 are pivotally connected,

near their lower ends, by means of a pin3`| and Y are provided, at theirupper ends respectively, with slots 36 and 38 which are angularly related. A pin 39, carried by the bifurcated lower end 35 of the operating link 34 which .embraces the upper ends of these gripper jaws, extends through y these two slots. The jaw 22 is provided with an upwardly extending rod 40` which engages a friction device 42, carried by the supporting member 30 and including a spring-pressed plunger 44, for controlling' the opening and closing movements of the gripper jaws 20 and 22 in the same manner as in the tensioning mechanism of the abovementioned patent and as will presently appear.

The lining-pulling gripper jaws 2 l, 23 are pivotally mounted on a pin 50 which is carried by a block 52. This block is slidably mounted in a groove 54, formed in the grippery jaw 22 below the slot 38 therein, and a spring friction plate 56 shaped to embrace this block bears against the bottom of the groove 54 so as to hold the pin 50 in place and also to urge the gripper jaws 2|, 23 yieldingly against the inside face of the side plate 28. A latch 58, pivotally `mounted on the gripper jaw 2|, is arranged to be moved into position for engagement with a cooperating shoulder f 50, formed on the lower end 35 of the operating link 34, by means of a leaf spring 82 supportedon the gripper jaw 22 when the parts are in the positions shown in Figs. 1, 2, 3 and 6. This latch is provided witha camming lug B3 which, at a predetermined time in the cycle of operation of the tensioning mechanism, rides over an inclined cam surface 64, formed on the gripper jaw 22, to cause the latch 58 to move out of engagement with the shoulder 60 and there'oy to disconnect the gripper` jaws-2|, 23 4from the-operating link 34. l

At their upper ends the gripper jaws 2|, 23are provided, respectively, with outwardly and upwardly diverging cam surfaces V10, 'I2 and the a coil spring 18 mounted on the side plate 28, see Fig. 6, which acts through a link 18 that is pivotally connected at one end to the gripper jaw 23. At its other end this link is connected to an arm formed integrally with a shaft 82. This shaft is journaled in a sleeve 84, pressed into the side plate 28, which sleeve also supports the coil spring 18. One end of this spring is anchored in this-side plate while the other end thereof engages a notch formed in a hexagonal nut 86 which is adjustably secured to the shaft 82 by means of a clamping screw 88. When this clamping screw is loosened, the nut 88 may be rotated to vary the tension of the spring 18 and hence the pull exerted on the gripper jaw 23 by the'link 18.

In addition to its action in closing the gripper jaws 2|, 23 the pull exerted by the spring 16 through the link 18 also holds the primary gripper jaws in engagement with a guide roll 90. This guide rollis journaled on a stud 92 that is pressfitted into a flange 94 formed on a bolt 86. The bolt 96 passes through a hole 98 formed in the side plate 28 and a nut |00 is provided for holding the roll in any position of adjustment to which it may be moved by rotating the bolt 93 which is provided with a slot 91, for this purpose. It will be understood that the roll is mounted eccentrically with respect to the axis of the bolt 96 and that its lateral position will be changed when. the bolt is rotated. The hole 9.8 is counter- .bored at |02 to receive the flange 84. The guide roll 90 cooperates with a cam surface |04 having an inclined portion |08 formed on the gripper jaw 22 for guiding the vertical movement of the tensioning mechanism in a manner to be explained below.

The link 18 is connected to the gripper jaw 23 by means of a pin |08 on which there is mounted a roll ||0. This roll is arranged to bear against a leaf spring ||2, supported on the gripper jaw 22 and which serves to augment the action of the coil spring 16 without, however, adding to the pressure of the cam surface F04 against the guide roll 90. For opening the gripper jaws 2|, 23 the pin 31 which connnects the jaws 20, 22 is provided with an angularly shaped projection |20 and the jaw 23 has a rounded camming lug |22. As will presently appear, at the completion of the tensioning action of the lining-pulling jaws 2|, 23, and substantia-lly at the time when the main jaws 20, 22 close on the upper materials, this camming lug will strike the projection |20 and cause the jaw 23 to swing away from the jaw 2| thereby releasing the grip of these jaws on the material` A complete operating cycle of the lasting unit and particularly of the improved tensioning mechanism will now be described. Referring rst to Fig. .1 of the drawings, in which the various parts are shown in positions assumed at the beginning of the operating cycle, the shoe on the last A is held upwardly Lby the operator, or by means of the shoe-supporting jack shown in the above-mentioned patent, against the anvil 25 which enters the inside angle formed by the rib R, the lasting margin of the upper materials enters between the opened gripper jaws 20, 22 and 2t, 23, and the nozzle 24 isiwithdrawn. For the purpose of illustrating the action of the liningtensioning gripper jaws 2| and 23, the lining L isrounded end '14, on the lower part vof the link 34, will move away from the inclined surfaces 10, 12, suiciently to permit the jaws 2|, 23 to close. After the lost motion, aiorded by this space between the latch 58 and the shoulder 60 has been taken up, as the slide 32 and link 34 continue to move upwardly, the jaw 2 i is swung in a counterclockwise direction toward the jaw 23 by the action of the latch l58, which is now in engagement with the shoulder 5D on the upwardly moving link Sil, while 'the jaw 23 is swung, in a clockwise direction and toward the jaw 2 by means of the spring 16 and also the spring 2 and these jaws are yieldingly closed on the upper material, as shown in Fig. 3. The friction device 42 at this time prevents upward movement of the jaws 2|] and 22 so that the pin 39, acting in the slots 36 and 38, begins to close these jaws also.

As the slide 32 continues its upward movement, the jaws 2| and 23, now yieldingly closed on the material, are elevated to exert an upward pullthereon. The jaw 2| has a smooth face 2|! which can slip over the upper U but the jaw 23 is provided with teeth 233, or otherwise roughened, so as to grip the lining L rmly and, as a result of the upward movement of these two jaws the lining will be tensioned and the fold F removed as the parts approach the positions shown in Fig. 4. At this stage in the cycle, the jaws 20, 22 will have been closed on the upper materials, by the continued upward movement of the slide 32 and the pin 39, to grip both the upper and lining firmly, these two jaws each being provided with a toothed, or otherwise roughened operating face, as shown. Just as the jaws 2|), 22 are thus closed, the camming lug |22 engages the projection |20 to open the jaws 2 l, 23, sufficiently to release their grip on the upper materials and, at substantially the same time, the latch 58 is moved out of engagement with the shoulder 6|), by the action of the cam surface 54 on the lug 53, to disconnect the jaws 2|, 23 from the operating link 31|.

Now, as the slide 32 completes its upward movement, the upper materials, i. e., the upper U and the lining L are both further tensioned by the grippers 2U, 22 and these tensioned materials are then laid inwardly against, and secured to, the rib R by means oi the fastener-inserting nozzle through which the staple s is drivenand clenched against the anvil 25. Fig. 5 shows the operating parts in the positions assumed just after the staple has been driven. As the gripper jaws 20, 22 are elevated after they have been closed to tension the .upper materials, they lare swung inwardly over the shoe bottom, to the right in Fig. 5, rst by the action of the guide roll 9G as it engages the inclined portion |06 of the cam surface |03, and nally by the engagement of the nozzle 24 with the upper materials.`

Immediately, after the staple has been driven, the slide 32 is moved downwardly and, during the initial portion of this downward'movement, the gripper jaws 2B and 22 are opened, thefriction device 142 now holding these jaws against downward movement and the pin 33 acting on the slots 36 and 38. When the rounded end 'M of the operating link Sil comes into engagement with the camming surfaces m and l2, the jaws 2|, 23 will be opened, the resistance to downward movement of these jaws provided by the friction plate 56 being suihcient to cause this opening action. Thereafter, and when the jaws 2|), 22 and 2|, 23 have been fully opened, these jaws are all moved downwardly as a .unit and .the parts are returned to their original positions as shown in Fig. 1 when the slide 32 has completed its downward move- 4 ment.

Having described the invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising two grippers, each having a pair of jaws adapted to engage both said upper and said lining, the jaws of one pair having a smooth face, for engaging the upper, and a roughened face, for engaging the lining, and the jaws of the other pair each having a roughened face for engaging the upper and lining, respectively, operating means common to both grippers, and connections between said operating means and the grippers constructed and arranged to cause said grippers, successively, to close on the upper materials and to move in a heightwise direction away from the bottom of the last.

2. Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an upper-tensioning gripper and means for operating said gripper to cause it to close on the upper and then to move in a heightwise direction away from the bottom of the last, a liningpulling gripper associated with the upper-tensioning gripper, said gripper having a jaw with a smooth face for engaging the upper and a jaW with a roughened face for engaging the lining, and connections between said operating means and the lining-pulling gripper arranged to cause said lining-pulling gripper to be operated to tension the lining before said upper-tensioning gripper is closed on the upper materials.

3. Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an upper-tensioning gripper and means for operating said gripper to cause it to `close on the upper materials and then to move in a heightwise direction away from the bottom of the last. a lining-pulling gripper slid-ably mounted on the upper-tensioning gripper, and connections including a latch between said operating means and the lining-pulling gripper arranged .to cause said lining-pulling gripper to be operated to tension the lining before said upper-tensioning gripper is closed on the upper materials.

4. Mechanism for tensioning upper materials,

y including an upper and a lining, over a last comprising an upper-tensioning gripper and means for operating said gripper to cause it to close on Ithe upper materials and then to move 4in a heightwise direction away from the bottom of the last, a lining-pulling gripper slidably mounted yon the upper-tensioning gripper, said gripper having a jaw with a smooth face for engaging :the upper and a jaw with a roughened face for engaging the lining, and connections including a latch between said operating means and the lining-pulling gripper arranged to cause said lining-pulling gripper to be operated to tension the lining before said upper-tensioning gripper is closed on the'upper materials.

5. Mechanism for tensioning upper materials,

including an upper and a lining, over a last ycomprising an upper-tensioning gripper and means for operating said gripper to cause it to close on the upper materials and then to move in a heightlatch between said operating means and the 1ining-pulling gripper arranged to cause said liningpulling gripper to be operated totension the lining,

andere and means associated with 'the upper-.tensioning gripper for disengaging said latch to terminate the tensioning action Iof said lining-pulling grippers substantially at the time when the upper-pulling grippers are closed on the upper materials.

6.- Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an .upper-tensioning gripper, operatingr means connected to said gripper and movable first to eect Closing of the gripper and, thereafter, movement thereof in a direction to tension the upper materials about the last, a lining-pulling gripper including a pair oi pivotally connected jaws slidably mounted on the upper-tensioning gripper, means tending to close said jaws, means associated with said operating means for opening said jaws, and connection-s between said operatingr means and said jaws so constructed and arranged that upon movement of said operating means said pair of jaws are rst closed and then moved bodily d with said operating means to tension the lining prior .to the operation of said upper-tensioning gripper.

7. Mechanism for tensioning upper materials. including an upper and a lining, over a last comprising an upper-tensioning gripper, operating means connected to the gripper and movable nrst to effect closing of said gripper and, thereafter, movement thereof in a direction to tension the upper materials about the last, a lining-pulling gripper 'including a pair of pivotally connected jaws slidably mounted on the upper-tensioning gripper, yieldable means tending to close said jaws, means associated with said operating means for opening said jaws, and connections between said operating means and said jaws so constructed and arranged that upon movement of said -operating means said pair of jaws are first yieldingly closed and then moved bodily with said operating means to tension the lining prior to the operation of said upper-'tensioning gripper.

S. Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an upper-tensioning gripper, operating means connected to the gripper and movable first to effect closing of said gripper and, thereafter, movement thereof in a direction to tension the upper materials about the last, a lining-pulling gripper including a pair of pivotally connected jaws slidably mounted on the upper-tensioning gripper, yieidable means tending to close said jaws, one of saidy jaws having a smooth face for engaging the upper and the other said jaw having a roughened face for engaging the lining, means associated with said operating means for opening said jaws, and connections between said operating means and said jaws so constructed and arranged that upon movement of said operating means said pair of jaws are rst yieldingly closed and then moved bodily with said operating means to tension the lining prior to the operation of said uppertensioning gripper. i

9. Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an upper-tensioning gripper, operating means connected to the gripper and movable iirst to effect closing of said gripper and, thereafter, movement thereof in a direction to tension the upper materials over the last, a lining-pulling gripper including a pair of pivotally connected jaws slidably mounted on the upper-tensioning gripper, yieldable means tending to close said jaws, cam means associated with said operating means for opening said jaws, and connections between said operating meansand `said .pair of E jaws so constructed and arranged that upon movement of said operating means said pair of jaws are rst yieldingly closed and then moved bodily with said operating means to tension the lining prior tothe operation of said upper-tensioning gripper.

10. Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an upper-tensioning gripper, operating means connected to the gripper and movable first to eiect closing of said gripper and, thereafter movement thereof in a direction to tension the upper materials over the last, a lining-pulling gripper including a pair of pivotally connected jaws slidably mounted on the upper-tensioning gripper, yieldable means tending to close said jaws, cam means associated with said operating means for opening said jaws, connections between said operating means and said pair of jaw-s so constructed `and arranged that upon movement of said operating means said pair of jaws are rst yieldngly closed and then moved bodily with said operating means, and means associated with said upper-tensioning gripper for opening said pair of jaws upon a predetermined movement of said operating means.

11. Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an upper-tensioning gripper, operating means connected to the gripper and movable rst to eect closing of said gripper and, thereafter, movement thereof in a direction to tension the upper materials over the last, a lining-pulling gripper including a pair of pivotally connected jaws slidably mounted on the upper-tensioning gripper, yieldable means tending to close said jaws, cam means associated with said operating means for opening said jaws, a latch for connecting said jaws to said operating means upon movement thereof sufficient to permit closing of said jaws, and means associated with said uppertensioning gripper for disengaging said latch to arrest movement of said jaws.

12.`Mechanism for tensioning upper materials, including an upper and a lining, over a last comprising an upper-tensioning gripper, operating means connected to the gripper and movable iirst to eect closing of said gripper and, thereafter, movement thereof in a direction to tension the upper materials over the last, a lining-pulling gripper including a pair of pivotally connected jaws slidably mounted on the upper-tensioning gripper, yieldable means tending to close said jaws, cam means associated with said operating means for opening said jaws, a latch connected to said jaws and adapted to engage a shoulder on said operating means upon movement thereof sucient to permit closing of said jaws by the yieldable means, means for disengaging said latch after apredetermined movement of said jaws by said operating means, and means associated with said upper-tensioning gripper for opening said jaws substantially as said upper-tensioning gripper is closed.

ROBERT H. LAWSON.

REFERENCES SHED The following referencesare of record in the le of this patent:

UNITED STATES PATENTS Number Y Name Date 460,394 Lake Sept. 28, 1891 1,396,005 Ashton Nov. 8, 1921. 

